[blackcat] L2 Ehlers Fisher Adaptive RSI

8 nov 2020

Level: 2

Background

John F. Ehlers introuced adding the Fisher Transform to the Adaptive RSI in his "Cycle Analytics for Traders" chapter 15 on 2013.

Function

The purpose of the Fisher transform is to take any indicator having a nominally zero mean and bounded between the limits of −1 to +1 and convert the amplitude so that the transformed indicator has an approximate normal probability distribution. The variable MyRSI ranges between zero and one, and therefore to accommodate the conditions for the Fisher transform, this variable must be translated and dilated to range between −1 and +1. If the MyRSI variable does not range fully between zero and one, you can shorten the RSI lookback period to be less than half the measured dominant cycle, or you can simply multiply it by a magnification factor as Dr. Ehlers have done in the code fragment. The amplifying factor was selected to make the indicator rarely exceed the two sigma points in the output. The amplified RSI is then limited to be within the range of −0.999 to +0.999 to avoid a computer crash, and then is used to compute the Fisher transform. The plus and minus two standard deviation levels are included in the indicator display.


Key Signal

Fish --> Fisher Adaptive RSI fast line
Trigger --> Fisher Adaptive RSI slow line

Pros and Cons

100% John F. Ehlers definition translation, even variable names are the same. This help readers who would like to use pine to read his book.

Remarks

The 61th script for Blackcat1402 John F. Ehlers Week publication.

Readme

In real life, I am a prolific inventor. I have successfully applied for more than 60 international and regional patents in the past 12 years. But in the past two years or so, I have tried to transfer my creativity to the development of trading strategies. Tradingview is the ideal platform for me. I am selecting and contributing some of the hundreds of scripts to publish in Tradingview community. Welcome everyone to interact with me to discuss these interesting pine scripts.

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